Apparatus of this type has been described in German Offenlegungsschrift 25 16 499. The wire from which the insulation is to be removed is inserted between two clamping jaws prior to cutting into the insulation with two knives and prior to removing the insulation. The apparatus makes it possible to remove the insulation from a wire, the conductor core of which has a cross section of only 0.14-1.5 mm2. It is considered a disadvantage of this apparatus that by clamping the insulation of the conductor on both sides, indentations and possibly even damage to the insulation may be caused. It is another disadvantage that, owing to cutting into the insulation only from two sides, the piece of insulation to be removed can be separated only partially and not in the form of a clear cut prior to tearing away such portion of the insulation from the remaining insulation. This may result in unacceptable conditions in the ensuing utilization of the wire from which the insulation was removed, for example when the insulation is not completely removed, the part of the insulation remaining must be manually removed prior to soldering, as otherwise reliable soldering would not be possible.
Further, the known apparatus does not allow for the removal of an insulation made from a very hard plastic from an electrical wire, so that the possibilities of using the known apparatus are very limited.